According to the briefing that the Beggar's Sect had provided him with, the Shadow Isles were in the Sirana Gulf, surrounded by the east coast of the Derschek Region.
Since he was approaching the Shadow Isles from the east, he would need to pass through the Derschek Region to get to the Isles.
According to the intelligence from the Beggar's Sect, the Derschek Region was one of the most volatile war-ridden regions in its geopolitical surroundings. The reason for it was actually quite simple.
Access to incredibly cheap covert and assassination services.
The Shadow Isles that were surrounded by the Derschek Region on three sides were filled with quality and elite covert operatives and assassins looking to gain the tutelage of the Silent Shadow. During their stay on the Shadow Isles in search of the Silent Shadow, these covert operatives and assassins made a living by doing what they did best.